Using resources Flashcards
sustainable development
meets needs of current gens without damaging lives of future generations
reduce env impact of manufacture
reduce energy needed
make processes more efficient
recycling
too damaged to reuse
separated by colour and type
crushed, melted , reshaped to form new products
lcas
look at different stages in a products life in order to assess its impact on the environment
main stages of lca
1)extracting and processing raw materials
2) manufacturing and packaging the product
3) using the product
4) disposing of the product
problem 1) lca
extraction can damage local environment
processing indirectly damages environment (huge amounts of energy required + pollutants released)
lca problem 2
energy use
pollution (CO)
production of waste products (usually useless and need to be disposed of)
lca problem 3
damage during lifetime (eg, pollution while driving car)
how long product is used for
lca problem 4
landfill- chemicals seep out + use up space which could be used for nature
burning- releases pollutants
both require energy for transportation
limitations of lca
almost impossible to quantify every step of a products life
also difficult to assess harm of each step
can be manipulated in support of a company
potable water
water thats safe to drink
not necessarily pure
often contains dissolved subtances
criteria of pw
low level of dissolved substances
pH between 6.5-8.5
no microorganisms in it
sources
fresh water (eg from rain)
surface water (rivers, lakes, reservoirs)
- easy to access , replaced frequently
ground water (aquifers)
treating fresh water
pass through wire mesh
pass through bed of sand and gravel (filter out smaller solids)
sterilised to kill any microbes
- bubbled through chlorine gas/ exposed to ozone or UV light
reverse osmosis
salt water passed through membrane
doesnt allow salt or ions through
left with pure water
